Nutrient 4.4 migration guide

This article provides a set of guidelines for migrating from version 4.3 to version 4.4 of Nutrient Android SDK. If you’re upgrading from a version earlier than 4.0, review the Android 4 migration guide first.

Digital signatures

The digital signing framework, which we introduced in Nutrient Android SDK 4, was partially rewritten to support external signature providers such as hardware security modules (HSMs) and other signing entities. Moreover, the signing APIs were extended to support the implementation of multi-step signing flows — for example, when user interaction is required during the signing process.

Several methods from the original digital signatures API have been deprecated. If your app uses a custom Signer subclass, we encourage you to migrate to the new interface.

The following resources should help you while you’re migrating to the new signing APIs:

  • Our digital signatures guide

  • The CustomSignatureProviderExample in our Catalog app, which gives a quick introduction to the new digital signing APIs

Deprecated Signing methods

To fully support the newly added APIs, we deprecated the following methods on the Signer and MemorySigner classes:

  • Signer _ signFormFieldAsync(com.pspdfkit.forms.SignatureFormField, java.security.KeyStore.PrivateKeyEntry, java.io.OutputStream) _ signFormFieldAsync(com.pspdfkit.forms.SignatureFormField, java.security.KeyStore.PrivateKeyEntry, com.pspdfkit.signatures.BiometricSignatureData, java.io.OutputStream) _ signFormField(com.pspdfkit.forms.SignatureFormField, java.security.KeyStore.PrivateKeyEntry, java.io.OutputStream) _ signFormField(com.pspdfkit.forms.SignatureFormField, java.security.KeyStore.PrivateKeyEntry, com.pspdfkit.signatures.BiometricSignatureData, java.io.OutputStream)

  • MemorySigner _ signFormFieldAsync() _ signFormField()

As a replacement, use the new signFormField() and signFormFieldAsync() methods on Signer.